A Long Term Evolution (LTE) system is a frequency division system which adopts Orthogonal Frequency Division Multiplexing (OFDM) as a basic multiple access multiplexing manner. In the system, there is little interference inside a cell due to the completely orthogonal frequency division. However, interference at the edge of a cell is relatively serious, thus spectral efficiency at the edge of a cell is concerned. At present, there are mainly three methods for processing the interference at the edge of a cell in LTE: interference randomization, interference elimination and interference coordination (elusion). The interference coordination becomes a mainstream technology for restraining the interference between cells, due to its simple realization, capability of being applied to various bandwidths and good effect on interference restraint.
Currently, the interference coordination generally employs frequency reuse schemes such as fractional frequency reuse and soft frequency reuse, which can effectively restrain common-frequency interference between cell edge users.
With the growing shortage of spectrum resource and the increasing user requirements on the Quality of Service (QoS), LTE-A, which is a follow-up evolution of LTE, puts higher demands on both cell average spectrum efficiency and cell edge spectrum efficiency. For the future wireless communication system, it is desired to realize full frequency reuse in addition to further improved performance of edge users, so as to obtain higher cell average spectrum efficiency at the same time. Moreover, an enhanced Physical Downlink Control Channel (ePDCCH) is introduced in LTE-A, that is, the transmission of the ePDCCH is allowed by using a part of resource in original Physical Downlink Shared Channel (PDSCH).